Electrolytic cell



March 15, 1938. B, BREN AN 2,111,041

ELECTROLYTIC CELL File'd May 14, 1935 FIG. 2

Patented Mar. 15, 1938 UNITED STATES PATENT OFFlCE 12 Claims.

My invention relates to electrolytic cells and more particularly to an improved method of sealing and venting electrolytic cells, as electrolytic condensers. Such electrolytic condensers usually have one or more film-forming electrodes surrounded by a suitable electrolyte, or multiple electrodes and electrolyte therebetween. The capacity elements of a condenser are usually put in a container, which may consist of a cylindrical tube of aluminum.

In service, such condensers have a metallic cap spun into at least one end of the container. The usual practice at present has been to use a gasket in sealing the cap to the top of the container, and a separate venting meansis usually provided, consisting of a fusible metal and an orifice in said cap or a rubber member having an orifice in said rubber member.

Another combination vent and sealing means now in use consists of a,gasket made by cutting out annular pieces of material from a sheet of cloth impregnated with a substance such as wax. Objection has been found in the use of this latter type of sealing and venting means, due to-the fact that the cloth itself may act as an effective seal and not have any venting characteristics, in case the cloth is too highly compressed when the cap and the end of the container are spun or forced together.

In my invention I have been able to overcome this latter difficulty and also to provide a positive spacing means between the cap face and the face of the end of the container. This is accomplished by roughening either of these faces or both and coating said roughened face or faces with a material such as wax, which, when an elevated temperature is attained in the operation of the condenser, will fiow from between the faces of the cap and the end of the container, permitting gases which develop within the condenser to escape without damage to the condenser when in operation. As a means of roughening, embossing or knurling is satisfactory.

In this way economy is eflected by the elimination of the use of cloth or such material. The roughening operation is accomplished at the same time the cap is formed, or at the same time the flange is formed on the end of the container subsequently, and before sealing, either one or both of these faces are coated with a substance such as wax, and a positive spacing means is secured.

Such a venting and sealing means is particularly applicable to the so-called wet condenser, or to any electrolytic cell which, in operation, is characterized by an elevation in temperature.

This elevation in temperature'may be due to a number of reasons, as is well known to those versed in the art; and, when arising from operating conditions, is always accompanied by gas within the condenser which may, if not relieved adequately, cause an explosion. Thus, this venting and sealing means operates in the nature of a safety device.

Another method of providing a spacing means for the metallic surfaces which are to be used as a vent is to sandblast one or more of these surfaces and then deposit a fusible substance, as wax, thereon: or metallic particles may be sprayed on one or more of these surfaces and wax deposited thereon subsequently; or the surfaces may be treated chemically and roughened, as by etching, and a fusible substance deposited thereon.

A further means of accomplishing the purpose of this invention is to cover the faces of the flange to be used in sealing with hard particles, as of sand or metal, having a fusible substance mixed therewith, or a layer of a fusible substance, as of Wax, deposited thereon, either before or subsequent to the operation wherein the particles are deposited thereon.

As another means, a layer of fusible substance may be deposited on one ormore of the metallic surfaces which are to be juxtaposed and a fibrous flock attached thereto, as by spraying an airblast while the fusible substance is in a partially liquid condition, so that the particles of flock will form a layer thereon and act as a spacing means.

In the drawing forming a part of this specification Figure 1 is a section showing the cap such as is ordinarily used for sealing the container of a cell of the type described. This cap may consist of aluminum or other metal which is formed in a punch press operation. At the same time this cap is formed into the shape shown in Figure 1, an embossed surface may be formed thereon by well-known means.

Figure 2 is an ordinary type wet electrolytic container wherein the container (5) of electrolyte (l) and the electrode (6), with ariser (l0) extending outward therefrom and having a sealing means (9), and surrounded by a neck (8), has a flange (4) at the top thereof. The shape of the flange (4) conforms to the shape of the embossed face (2) of the cap (I). The usual method of attaching the cap (I) to the container (5) is by spinning the flanges (2 and 4) together, after the faces thereof have been placed together. Prior to this spinning operation a layer of fusible substance (3) such as waxis coated,

as with spraying or with a brush, onto the peripheral flange of the cap l Referring to Figure 3 of my drawing, wherein the manner of sealing is shown, the embossed face (2) of the cap (I) is mechanically attached to the flange (4) of the container in such a way that when an elevation in temperature, which may result from operation of the condenser, is attained, the fusible substance, such as Wax (3), melts and flows by gravity or/and gas pressure from within the interstices or orifices produced by the embossing (2).

While I have described a specific instance of my invention, and while this illustrates its application specifically, I do not wish to be limited either in constructive details or application thereby, but desire my claims to be construed as broadly as permissible, in view of the prior art.

What I claim is:-

1. A sealing and venting device for an electrolytic cell comprising rigidly shaped surfaces, spaced apart by a. rigid porous means, the pores thereof being filled in with a fusible sealing material.

2. A venting and sealing means for an electrolytic cell comprising juxtaposed surfaces, one of which is embossed, the embossings thereof being filled with a fusible substance.

3. A venting and sealing means for an electrolytic cell comprising a metallic porous spacing means, the orifices of which are sealed with a fusible substance.

4. A fusible vent consisting of a. porous metallic structure, the pores of which are sealed with wax.

5. A vent for an electrolytic condenser comprising a roughened metallic surface sealed with a fusible substance against an adjacent metallic surface.

6. A vent for an electrolytic cell comprising a non-compressible porous spacing means, the pores thereof being sealed with a fusible substance.

7. In combination, a vent and seal comprising porous, rigidly-spaced metallic surfaces sealed with a fusible material therebetween.

8. A seal and vent comprising an embossed metallic surface juxtaposed on asecond metallic surface, and a layer of a fusible material therebetween. v

9. A vent and seal comprising a reticular metallic spacer and a fusible filler therefor, which acts as a seal.

10. In combination, in an electrolytic device, spaced metallic surfaces, at least one of which surfaces is roughened, and a fusible, liquid tight seal disposed between said metallic surfaces.

11. An electrolytic cell comprising in combination a container for electrolyte, a closure therefor, said container and closure having juxtaposed surfaces, rigid reticular spacing means for maintaining said juxtaposed surfaces in spaced relationship, and a layer of fusible sealing material disposed between said surfaces.

12. An electrolytic cell comprising a container for electrolyte, a closure member therefor, said container and closure having juxtaposed surfaces, at least one of said surfaces being roughened and the space between said surfaces being sealed with a fusible material.

JOSEPH B. BRENNAN. 

